[PATCH 5.10 513/717] vfio/pci: Move dummy_resources_list init in vfio_pci_probe()

Greg Kroah-Hartman
2020-12-28T14:25:08Z

From: Eric Auger <eric.auger@redhat.com>

commit 16b8fe4caf499ae8e12d2ab1b1324497e36a7b83 upstream.

In case an error occurs in vfio_pci_enable() before the call to
vfio_pci_probe_mmaps(), vfio_pci_disable() will try to iterate
on an uninitialized list and cause a kernel panic.

Lets move to the initialization to vfio_pci_probe() to fix the
issue.

Signed-off-by: Eric Auger <eric.auger@redhat.com>
Fixes: 05f0c03fbac1 ("vfio-pci: Allow to mmap sub-page MMIO BARs if the mmio page is exclusive")
CC: Stable <stable@vger.kernel.org> # v4.7+
Signed-off-by: Alex Williamson <alex.williamson@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/vfio/pci/vfio_pci.c | 3 +--
1 file changed, 1 insertion(+), 2 deletions(-)

--- a/drivers/vfio/pci/vfio_pci.c
+++ b/drivers/vfio/pci/vfio_pci.c
@@ -161,8 +161,6 @@ static void vfio_pci_probe_mmaps(struct
int i;
struct vfio_pci_dummy_resource *dummy_res;

- INIT_LIST_HEAD(&vdev->dummy_resources_list);
-
for (i = 0; i < PCI_STD_NUM_BARS; i++) {
int bar = i + PCI_STD_RESOURCES;

@@ -1966,6 +1964,7 @@ static int vfio_pci_probe(struct pci_dev
mutex_init(&vdev->igate);
spin_lock_init(&vdev->irqlock);
mutex_init(&vdev->ioeventfds_lock);
+ INIT_LIST_HEAD(&vdev->dummy_resources_list);
INIT_LIST_HEAD(&vdev->ioeventfds_list);
mutex_init(&vdev->vma_lock);
INIT_LIST_HEAD(&vdev->vma_list);